The request comes after Myanmar military admitted that some of its soldiers were involved in the murder of 10 captured Rohingya men in western Rakhine state.
In a rare move, a military investigation report on Wednesday admitted its soldiers and ethnic villagers had killed 10 captured Rohingya people and buried them in a mass grave near Inn Din village in Maungdaw township of Rakhine State in September.
In a statement, the EU delegation in the country said: “These brutal killings confirm the urgent need for a throughout and credible investigation” into all alleged rights abuses in the northern part of Rakhine state where military operations have forced at least 650,000 people, mostly Rohingya Muslims, fled cross-border to neighboring Bangaldesh since August last year.
“Impunity of perpetrators of such serious human rights violations must end,” it said.
It called on the government of Myanmar to “fully cooperate with Human Rights Council’s independent international fact-finding mission and other independent observers, including journalists and to provide for their full, safe and unhindered access to all conflict areas without delay”.
Amnesty International welcomed the admission by the military, saying it is a sharp departure from its policy of blanket denial of any wrongdoing during the operation in Maugndaw areas.
“However, it is only the tip of the iceberg and warrants serious independent investigation into what other atrocities were committed amid the ethnic cleansing campaign that has forced out more than 655,000 Rohingya from Rakhine State since last August,”Amnesty International’s Regional Director for Southeast Asia and the Pacific James Gomez said in statement on Wednesday.
It said Amnesty International and others have documented overwhelming evidence that far beyond Inn Din, in villages and hamlets across northern Rakhine State, the military has murdered and raped Rohingya, and burned their villages to the ground.
“These acts amount to crimes against humanity and those responsible must be brought to justice,” James Gomez.
The Rohingya, described by the UN as the world's most persecuted people, have faced heightened fears of attack since dozens were killed in communal violence in 2012.
Since 25 Aug. 2017, some 650,000 refugees, mostly children and women, fled Myanmar when Myanmar forces launched a crackdown on the minority Muslim community, according to the UN.
At least 9,000 Rohingya were killed in Rakhine state from Aug. 25 to Sept. 24, according to Doctors Without Borders.
In a report published on Dec. 12, 2017, the global humanitarian organization said the deaths of 71.7 percent or 6,700 Rohingya were caused by violence. They include 730 children below the age of 5.
The UN has documented mass gang rapes, killings -- including of infants and young children -- brutal beatings, and disappearances committed by security personnel. In a report, UN investigators said such violations may have constituted crimes against humanity.